Lua

SSH Tunnel Listener Activity Log

Demonstrates the listener-log properties KeepAcceptLog, AcceptLog, and AcceptLogPath, which record the activity of the background listener thread started by BeginAccepting.

Note: The log paths are relative to the application's current working directory. Absolute paths may also be used.

Background: Because the listener runs on a background thread, an activity log is often the only practical way to see what it is doing — which connections it accepted and when. KeepAcceptLog must be enabled for the in-memory AcceptLog to be populated; AcceptLogPath is an independent file-based log that persists across the run. This log covers the listener specifically, as distinct from the TunnelLog that records the SSH tunnel threads.

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Lua

local chilkat = require("chilkat")

-- Demonstrates the SshTunnel listener-log properties KeepAcceptLog, AcceptLog, and AcceptLogPath.
--
-- These log the activity of the background listener thread started by BeginAccepting.

local tunnel = chilkat.SshTunnel.new()

-- Retain the listener activity log in memory so it can be read from the AcceptLog property.
tunnel.keep_accept_log = true

-- Optionally also write the listener activity to a file (separate from the in-memory log).
tunnel.accept_log_path = "qa_output/accept.log"

tunnel.dest_hostname = "db.internal.example.com"
tunnel.dest_port = 5432

local sshPort = 22
local success = tunnel:connect("ssh.example.com", sshPort)
if not success then
    print(tunnel.last_error_text)
    return
end

-- Normally you would not hard-code the password in source.  You should instead obtain it
-- from an interactive prompt, environment variable, or a secrets vault.
local password = "mySshPassword"

success = tunnel:authenticate_pw("mySshLogin", password)
if not success then
    print(tunnel.last_error_text)
    return
end

local listenPort = 1080
success = tunnel:begin_accepting(listenPort)
if not success then
    print(tunnel.last_error_text)
    return
end

-- ... the listener accepts connections for a while ...

-- Read the accumulated in-memory listener log.
print(tunnel.accept_log)

local waitForThreadExit = true
success = tunnel:close_tunnel(waitForThreadExit)
if not success then
    print(tunnel.last_error_text)
    return
end